Motor driven apparatus for the automatic closing of a switch



May 18, 1965 J. E. ISCHUSTER 3,184,565

MOTOR DRIVEN APPARATUS F011 THE AUTOMATIC CLOSING OF A SWITCH Filed April 9, 1963 s Sheets-Sheet 1 INVENTOR.

- BY @904 a ter E 2 ATTORNEY y ,1965 J. E. SCHUSTER 3,184,565-

E ARATUS F0 AUTOMATIC CLOSING OF A SWITCH Filed April 9, 1963 5 Sheets-Sheet 2 INVENTOR May 18, 1965 J. E. SCHUSTER MOTOR DRIVEN APPARATUS FOR THE AUTOMATIC CLOSING OF A SWITCH I5 Sheets-Sheet 3 Filed April 9, 1963 CLOSED L M m w 0 h VV M Q l F1III|L z 4 4 8 3 4 Q m 4 V w 8 t V/ Ll fi l m 3 INVENTOR- BY (904 g 824%! VQJJJZVKQ- ATTDRNE United States Patent 3,184,565 MUTGR DRKVEN APPARATUS FOR THE AUTOMATIC CLOdlNG OF A SWITCH John Edward Schuster, Washington, D.C., assignor to Atlantic Research Corporation, Fairfax, Va., :1 corporation of Virginia Filed Apr. 9, 1963, Ser. No. 271,754 6 Qlaims. (Cl. 200-92) This invention relates to apparatus for the automatic closing or resetting of switches such as those found in electrical transmission systems. It is particularly wellsuited to be used with circuit breakers, such as reclosers, when automatic resetting of this type of switch is desired.

The hazards that a human may encounter when manually resetting switches used in electrical transmission and distribution systems require that a safe technique be followed during this operation. Better yet, it has been found that the ideal solution is to eliminate these hazards altogether through the employment of automatic resetting apparatus which does not need a human operator to manually reset these switches. There have been previous designs of automatic switch closing apparatus which have accomplished their purpose insofar as the safety aspects of the problem are concerned; however, these esigns have often failed to take into full consideration the operation of the switch to which they are attached. For example, a circuit breaker, such as an automatic circuit recloser built by the Line Materials Co. and other manufacturers, is constructed with internal contacts which open automatically upon the occurrence of a fault on the electrical transmission line to which the recloser is connected. This recloser has an external hand lever mounted onto a shaft, the internal construction of the recloser being such that, to open, this shaft must rotate. it automatic switch closing apparatus is connected to either this external hand lever or shaft and subsequently becomes inoperative or jams while the re closer is in the closed position, the occurrence of a fault can fail to open the recloser. This failure is due to the inability of the shaft to rotate because of the locking effect which the jammed or inoperative automatic closer has on the recloser hand lever or shaft. The present invention is designed to overcome this disadvantage by having as one of its objects a means for the positive disengagement of the switch and automatic switch closing apparatus after the closing operation.

it is also known that when a circuit breaker employing manual resetting means is opened by the occurrence of a fault, it remains in this open condition until such time as maintenance personnel can locate and reset the circuit breaker. Not only is this a costly procedure but often results in lengthy outage time for the circuit which the breaker is protecting. Accordingly a second object of this invention is to reduce circuit outage times and maintenance costs by providing automatic switch closing apparatus which is capable of being used in remote control systems.

A further object is to provide switch closing apparatus which requires no mechanical modifications of the switch during installation and which is designed to operate with a graduated series of switch structures.

Another object is to provide a simple, inexpensive automatic switch closer, made of relatively few parts and not encumbered with complicated crank, spring and linkage movements, which is compact in construction and portable to permit field installation.

3,184,565 Patented May 18, 1965 Other objects and advantages will become apparent by a reading of the following specification taken in conjunction with the drawing wherein:

FIGURE 1 is a side elevation of the switch closing apparatus mounted to coact with the switch structure;

FIGURE 2 is a perspective view of the apparatus showing only the hand lever and shaft of a switch structure;

FIGURE 3 is a wiring diagram for the automatic switch closing apparatus; and

FIGURES 4a, 4b and 4c are a series of three diagrams showing the relative positions of certain structural elements during the closing cycle.

The automatic switch closing apparatus broadly comprises a drive motor, whose shaft has mounted thereon a driving gear, and a driven gear designed to be engaged and driven by the driving gear. Means responsive to the rotation of this driven gear are provided for closing the switch during operation of the motor. Rotation of the driven gear through an angle of rotation suflicent to close the switch actuates means for disengaging the driving and driven gears.

Referring to FIGURES 1 and 2 there is shown a preferred embodiment of the automatic switch closing or resetting apparatus which is designed to be installed onto a circuit breaker such as arecloser. The casing 16 of the automatic switch closer can be made of steel or other rigid material and is designed as a weatherproof body when the hinged access door 12 is closed. Extending from the rear face of the casing 10 is an L- shaped mounting plate 14 having holes 16 which, together with the holes 18 in the rear face of the casing 10, cooperate with set screws 20 in mounting the apparatus onto the hand lever housing 22. The housing 22, shown in dotted-line form in FIGURE 1, is formed as a three-sided extension of recloser 1M and acts as a covering for the recloser hand lever as and its shaft 28. For field installation, as when the recloser is mounted on a utility pole, it generally requires the removal of a front cover plate (not shown) from the hand lever housing 22 and the mounting of the automatic switch closer onto this housing.

Within the casing in is a motor mount 3% having a yoke portion 32 extending upwardly and embracing the motor 34 at diametrically-opposed pivots 36, one of these pivots being shown in FEGURE 1. The drive shaft 38 of the motor 34 has formed thereon a worm 40 designed to mesh with worm gear 42 when the motor and shaft are pivoted upwardly. Worm 4t) is driven by motor 34 and is the driving gear for worm gear d2. Worm gear 42 can thus be termed a driven gear. The pivot points on the motor 34- are positioned off center to maintain the worm 4t) and worm gear 42 out of mesh when the motor is deenergized. The actual pivot ing of the motor 34 to cause engagement of the worm and worm gear is accomplished by solenoid 44. The armature or plunger 4a of the solenoid as extends out wardly through the arms of a Y-shaped lever 43 and is retained in this position by retainer ring 59. The base of the lever 48 is attached to motor 34 to provide the mechanical link between the motor and solenoid.

The Worm gear @2, here being shaped as a sector gear, is concentrically mounted with spur gear 52 on shaft 54. The shaft 54 is journaled in gear bracket 56 and in the rear face of the casing it A second spur gear 53 meshes with spur gear 5t and is mounted on shaft 66 which is journaled in another gear bracket 62 and also in the rear face of casing it). This shaft (it),

snsases though, extends through the casing into the housing 22 and has rigidly mounted thereon an elongated lever or actuator arm Arm is adapted or shaped to engage the hand lever 26 by the provision of threaded holes as at its outer extremity and a removable actuator pin This pin abuts the hand lever 2% during the automatic closing cycle. While the arm 64 could be bent or formed as an L-shape to abut the hand lever 26 without the addition of a pin as, it has been found that the pin is preferred because the apparatus is then capable of being used with a graduated series of reclosers having different size hand levers The plurality of holes 56 permit placing of the actuator pin 68 in the hole which will provide the maximum possible leverage with a particular hand lever 26.

A microswitch 7t is adjustably retained in the casing lit by set screw 72 which permits adjustment of the microswitch mounting block 14 to insure that the microswitch 7b is opened and closed at the proper times. Switching of microswitch '7tl is accomplished through the action of pins 73 and fill on the cam lever 76. Also mounted on the casin are relay 82, whose operation is discussed in the description of FIGURE 3, and protective fuse 84.

FEGURE 3 shows the wiring diagram of the apparatus and a partial schematic of the external circuit. The motor 34, solenoid d4, relay 82 are connected in parallel and form a series circuit with the fuse 8d and microswitch 7%. The relay is formed as a locking relay and consists of winding 38 and contact 9%. Lead 2 is connected externally to an alarm relay 94 which operates when the recloser is opened. The switch closing apparatus is operated by control switch 86 connected to relay 82 through lead 96. The locking relay 82 is preferred because it eliminates the necessity of maintaining the switch S6 closed during the closing cycle. Switch 86 can be a push button located at the base of a utility pole or can be the contact of a control relay 98, as shown. Control relay 93 is preferably connected to a central control station by a direct electrical line or a radio link, as desired. When the opening of the recloser closes microswitch '76, as later described, the alarm relay is actuated to close contact 100 completing a circuit to the control station and there indicating the outage condition. An operator, after learning of the open condition of the recloser, and undertaking whatever investigation is required, operates his equipment to actuate relay 98. Contact 86 closes, the switch closing apparatus is activated and the recloser is reset. This entire procedure entails only a fraction of the maintenance time normally required and thus greatly reduces the outage time of the distribution network protected by the recloser.

The operation of the overall automatic switch closing apparatus will now be described. Assuming that the recloser 24 has been opened by a fault in the transmission or distribution network, the recloser hand lever 26 will have fallen to the position shown in FIGURE 4a and the actuator arm 64 will lie adjacent to the hand lever as as shown. Microswitch '74) will have been closed by pin 80 abutting and pivoting cam lever 76 out of engagement with the microswitch detent. The motor 34 and solenoid 44 are now in condition to be energized by the closing of switch 36. The closing of microswitch 7t? also completes a circuit through alarm relay 94 for the purpose explained in the discussion of FIGURE 3. When switch 86 is closed current flows through the motor 34 and solenoid 44, energizing both of these devices. Solenoid plunger 46 retracts, pivoting motor 34 to bring the now rotating worm 49' into engagement with worm gear 42. Worm gear 42 begins to rotate counterclockwise, as viewed in FIGURE 1, and spur gear 52 follows. Spur gear 58, in mesh with gear 52, rotates clockwise and since gear 5?; and actuator arm 64 are mounted on the same shaft of the arm 64 begins to swing in a wide clockwise arc. The actuator pin 68 is in abutting engagement with hand lever 26 and this lever begins to rotate or swing upward towards the position shown in FIGURE 4b. Shaft 28 rotates with lever and the recloser begins to reset.

FEGURE represents the position assumed by the hand lever 26 when the recloser has been reset or closed. The hand lever 26 therefore overtravels the closed position in travelling to the position of FIGURE 415. At this position gear 52 has rotated sui fici-ently to cause pin 73 to pivot cam lever 7a to open the microswitch 7d, thereby deenergizing the motor 34 and solenoid 44. No longer restrained by the solenoid plunger 46, the motor pivots downwardly under the camrning or wedge action of the still rotating worm it? and the teeth of worm gear 42. This causes a positive disengagement of the worm 4d and worm gear 42. Simultaneously, the removal of a positive upward force on hand lever 25 permits it instantaneously to reverse its direction of rotation and this lever drops to the position shown in FIGURE 4c and the recloser is reset.

Considerable force is generated when the hand lever 26 drops to this last position because of the internal construction of the recloser 24. This force, when imparted to the actuator pin as is sufficient to push the arm 64 down to substantially the position shown in FIGURE 4c thus eliminating any contact between the hand lever and the automatic switch closing apparatus. This separation of these two structures insures that upon the occurrence of a subsequent fault the recloser will not be prevented from opening due to :the automatic switch closing apparatus. It can be seen that if the pin 68 abutted the hand lever 26 in the closed position, internal jamming of the apparatus could prevent the opening of the recloser by preventing the rotation of shaft 23. But with the arm 64 in the posi ion shown in FIGURE 40, the lever 26 will be moving when it contacts the pin 68 and the torque on shaft 28 will be so great as to overcome any impediment created by a jammed or frozen apparatus. The force of the hand lever upon contacting the pin would either clear the jammed apparatus or bend or break pin 68 in moving to the open position. In fact, it is possible to make pin 68 a shear pin designed to break upon contact by the hand lever during a jammed condition of the automatic switch closing apparatus.

The position of the actuator arm 64 shown in FIG- URE 40, when the recloser is in the closed position, represents the approximate travel of this arm under the applied force of the hand lever 26 in dropping from the overtravel to the closed position. It is preferred that this applied force will not cause arm 64- to travel all the way to the position of FIGURE 4a because pin will pivot cam lever '76 out of engagement with the microswitch detent and give a false indication of an open condition by the energization of alarm relay 94. In practice it has been found that the friction and mass of the gearing in the automatic switch closing apparatus is sufhcient to prevent the travel of the arm 64 to the open position of FIGURE 4a. However, if necessary, spring or other retarding means could be employed to prevent movement of the arm 64 to this position. When a subsequent fault occurs in the transmission line, the hand lever 26 is still free to drop to FIGURE 4a because the internal friction and mass of the switch closer gears, even with the inclusion of the above-mentioned supplementary retarding means, is essentially a negligible resistance when compared with the force on the hand lever 26. The actuator arm 64 will be carried to the position of FIGURE 4a by the hand lever 26 and the apparatus is once again in condition to automatically reset the recloser.

While it has been stated that the worm 4t and worm gear 42 normally become disengaged through their camming or wcdging action, the aforedescribed instantaneous or abrupt reversal of direction of the hand lever 26 provides insurance for the disengagement of these gears.

This abrupt reversal of rotation is similar to a shock or sudden force being applied through the actuator arm and gearing to the Worm gear 42, the resultant effect being to thrust worm 40 downwardly out of engagement with worm gear 42. Of course, once the worm 40 and worm gear 42 have become disengaged, the off-center mounting of the motor 34 prevents reengagement until the solenoid 44 is again actuated.

The preferred embodiment just described employs the use of a mechanical lever to abut the switch handle in the closing operation. While this embodiment enables rapid field installation by requiring no modification of the switch, it is readily seen that the sector gear 42 can be mounted elsewhere. For example, this gear could be factory or field installed on the switch handle shaft 28, thereby eliminating the actuator arm and gear train. However, since the great majority of these units will be installed in the field on unmodified switches, the disclosed configuration has been found to be the most advantageous embodiment.

It is to be noted that while provision has been made for the automatic resetting of the recloser by this invention, manual operation of the recloser is still possible through the manipulation of hand lever 26. This manual operation can be performed independent of any action of the automatic switch closing apparatus.

The motor 54 is conventional in construction and rotates at approximately 2000 rpm. This speed gives a closing time within one-half to one second depending upon the particular gearing ratios used in the gear train. This time range has been found to be the preferred one for closing recloser-type switches. At resetting times of less than one-half second, the construction of some reclosers is such that the internal cocking mechanism may fail to operate, requiring repeated actuation of the switch closing apparatus until resetting finally occurs. However, a recloser is but one example of a switch or circuit breaker with which this invention can be used and, obviously, if a change in switch closing time is required, one skilled in the art could make the necessary modifications, such as in the motor speed or gear ratio. Additionally, other changes and modifications may occur without departing from the spirit and scope of this invention.

I claim:

1. An electrical switch having an external shaft and manual operating means connected to said shaft, said manual operating means having a first rest position when said switch is open and a second rest position when said switch is closed, automatic switch closing apparatus cooperating with said switch, said apparatus comprising a driven gear, a lever mechanically connected to said driven gear and shaped to abut said manual operating means during automatic closing of said switch, a motor having a shaft, a driving gear mounted on said shaft, means connected to said motor for engaging said driven gear and driving gear upon energization of said motor thereby rotating said driven gear and pivoting said lever to move said manual operating means from said first rest position towards said second rest position, means permitting overtravel of said manual operating means past said second rest position before said driven and driving gears become disengaged whereby said lever is forcibly separated from abutting engagement with said manual operating means when said last-named means returns to said second rest position.

2. An electrical switch having an external shaft and manual operating means connected to said shaft, said manual operating means having a first rest position when said switch is open and a second rest position when said switch is closed, automatic switch closing apparatus cooperating with said switch and having a driven gear, a lever mechanically connected to said driven gear and adapted to abut said manual operating means during automatic closing of the switch, a pivotally-mounted motor having a shaft, a driving gear mounted on said shaft, a solenoid having a plunger, said plunger being mechanically connected to said motor to pivot said motor upon energization of said solenoid, means for energizing said motor and solenoid thereby engaging said driving and driven gears to swing said lever and move said manual operating means from said first rest position to said second rest position.

3. A device as claimed in claim 2 wherein said driving gear is a worm and said driven gear is a sector worm gear.

4. Automatic switch closing apparatus for use with a switch of the type having external manual means for operating the switch, said apparatus comprising a motor having a shaft, said motor designed to rotate said shaft in one direction only, a driving gear mounted on said shaft to rotate with said shaft in said one direction, a driven gear, a gear shaft, said driven gear being mounted on said gear shaft to turn said gear shaft when driven by said driving gear, means connected to said motor for engaging said driving gear and said driven gear upon energization of said motor, means responsive to the rotation of said driven gear and gear shaft when said driven gear is engaged by and being driven by said driving gear for closing said switch, and means for disengaging said driving and driven gears after rotation of said driven gear through an angle of rotation sufficient to move said closing means to close the switch.

5. Automatic switch closing apparatus for use with a circuit breaker having an external handle for operating the circuit breaker, said handle being designed to move from a first position when the circuit breaker is open to a second position when the circuit breaker is closed, said apparatus comprising a motor having a shaft, a driving gear mounted on said shaft, a driven gear, said driving gear and said driven gear being normally disengaged, circuit means for energizing said motor, means for engaging said driving gear and said driven gear when said motor is energized, means connected to said driven gear and responsive to its rotation to close the circuit breaker thereby moving said handle from its first position to its second position, and means for disengaging said driving and driven gears after rotation of said driven gear through an angle of rotation suflicient to move said responsive means to close said circuit breaker.

6. A device as claimed in claim 2 further comprising means for disengaging said driving and driven gears after rotation of said driven gear through an angle of rotation sufiicient to move said lever to close said switch.

References Cited by the Examiner UNITED STATES PATENTS 1,934,665 11/33 Goldsborough 200-92 2,706,915 4/55 Rosenberg 20047 X 2,864,911 12/58 Brumfield 200-92 BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner. 

1. AN ELECTRICAL SWITCH HAVING AN EXTERNAL SHAFT AND MANUAL OPERATING MEANS CONNECTED TO SAID SHAFT, SAID MANUAL OPERATING MEANS HAVING A FIRST REST POSITION WHEN SAID SWITCH IS OPEN AND A SECOND REST POSITION WHEN SAID SWITCH IS CLOSED, AUTOMATIC SWITCH CLOSING APPARATUS COOPERATING WITH SAID SWITCH, SAID APPRATUS COMPRISING A DRIVEN GEAR, A LEVER MECHANICALLY CONNECTED TO SAID DRIVEN GEAR AND SHAPED TO ABUT SAID MANUAL OPERATING MEANS DURING AUTOMATIC CLOSING OF SAID SWITCH, A MOTOR HAVING A SHAFT, A DRIVING GEAR MOUNTED ON SAID SHAFT, MEANS CONNECTED TO SAID MOTOR FOR ENGAGING SAID DRIVEN GEAR AND DRIVING GEAR UPON ENERGIZATION OF SAID MOTOR THEREBY ROTATING SAID DRIVEN GEAR AND PIVOTING SAID LEVER TO MOVE SAID MANUAL OPERATING MEANS FOR SAID FIRST REST POSITION TOWARDS SAID SECOND REST POSITION, MEANS PERMITTING OVER- 